我们有一个服务在同一个单独的服务器上命中几个dbs。该服务失败了，但是mysql没有中止所有连接，并且在很长一段时间内保持打开状态。下面是一个mysql日志。我们可以根据连接ID看到最后一行报告的连接应该已经在00:01中止了其余部分，但是它挂了2个多小时。
110216 0:00:01 [Warning] Aborted connection 11864307 to db: 'foodb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865442 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864559 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11863856 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865445 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864581 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865447 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864566 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865451 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865446 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865444 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864565 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865490 to db: 'foodb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864251 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864299 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864303 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865486 to db: 'foodb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864304 to db: 'foodb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864560 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11864268 to db: 'foodb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865055 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865443 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:01 [Warning] Aborted connection 11865450 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:02 [Warning] Aborted connection 11865448 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 0:00:02 [Warning] Aborted connection 11865485 to db: 'foodb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
110216 2:11:17 [Warning] Aborted connection 11865449 to db: 'bardb' user: 'db_user' host: '10.234.1.15' (Got an error reading communication packets)
现在，假设这是mysql的问题，鉴于以下超时设置，是否有任何可能导致此问题的原因？
mysql> show variables like '%time%';
+----------------------------+-------------------+
| Variable_name | Value |
+----------------------------+-------------------+
| connect_timeout | 10 |
| datetime_format | %Y-%m-%d %H:%i:%s |
| delayed_insert_timeout | 300 |
| flush_time | 0 |
| innodb_lock_wait_timeout | 600 |
| innodb_rollback_on_timeout | OFF |
| interactive_timeout | 28800 |
| lc_time_names | en_US |
| long_query_time | 5 |
| net_read_timeout | 30 |
| net_write_timeout | 60 |
| slave_net_timeout | 3600 |
| slow_launch_time | 2 |
| system_time_zone | GMT |
| table_lock_wait_timeout | 50 |
| time_format | %H:%i:%s |
| time_zone | SYSTEM |
| timed_mutexes | OFF |
| wait_timeout | 28800 |
+----------------------------+-------------------+
mysql> show variables like '%packet%';
+--------------------+----------+
| Variable_name | Value |
+--------------------+----------+
| max_allowed_packet | 16777216 |
+--------------------+----------+
答案 0 :(得分：1)
您的max_allowed_size必须是默认的1M，并且您使用大量数据，blob或其他内容进行了一些查询。将该值增加到8M（最大限制为1GB）。
将wait_timeout减少到50左右。
wait_timeout is “服务器在关闭之前等待非交互式连接活动的秒数。此超时仅适用于TCP / IP和Unix套接字文件连接，而不适用于使用命名管道建立的连接，或共享存储器“。 Details